class Person{
  private name: string
  protected age: number
  public gender: string

  constructor(name: string, age: number, gender: string){
    this.name = name
    this.age = age
    this.gender = gender
  }

  show01(){
    console.log(this.name)
  }
}

class Student extends Person{
  
  show(){
    console.log(this.gender)
    console.log(this.age)
    // console.log(this.name)
  }
}


let s = new Student('zhangsan', 23, 'nv')

s.gender
// s.age


s.show()
s.show01()
